Condensing apparatus



Jan. 2, 1962 G. A. DALIN CONDENSING APPARATUS Filed Sept. 19, 1956 ATTORNEYS States Patent 3,015,474 CONDENSING APPARATUS George A. Dalin, 1563 Van Ness Terrace, Union, NJ. Filed Sept. 19, 1956, Ser. No. 610,807 6 Claims. (Cl. 25730) This invention relates to apparatus used for condensing vapors in distillation operations and of the reflux type, which returns the condensate to the vessel from which the vapors issue. More particularly, the invention is concerned with reflux condensing apparatus containing a novel combination of features, the use of which makes it possible to carry out distillation at a greatly increased rate without danger of flooding.

Reflux condensing apparatus is frequently fitted to vessels or kettles, in which liquid is boiled, in such manner that the vapor traveling from the kettle to the condenser and the condensate returning from the condenser to the kettle must pass simultaneously through the same opening or passage. It the cross-section of the opening or passage is too small to permit the free flow of the volumes of vapor and condensate in opposite directions, the condensate will be unable'to descend against the rising vapor and will finally be blown out of the top of the condenser. Such an action is called flooding and it results in loss of material and may give rise to fire and explosion. With distilling apparatus equipped with condensers as now made, flooding can be avoided by restricting the rate of heating the kettle, so that a relatively small volume of vapor is generated, but such a procedure results in prolonging the time required for a given operationv Another possible method of avoiding flooding involves constructing kettles with larger openings and making condensers with correspondingly large connecting means, but such an expedient would require scrapping present equipment and replacing it at higher cost and would be too expensive for general adoption.

The present invention is directed to the provision of condensing apparatus suitable for use with ordinary kettles and containing a novel combination of features, the use of which obviates the danger of flooding, even though the distillation is carried on at a greatly increased rate. In apparatus embodying the invention, the desired result is obtained by providing means by which the condensate may return to the kettle while out of contact with the vapors issuing from the kettle, and, since the returning liquid is not exposed to the action of the vapors, the liquid cannot be held back by the vapors and eventually carried out of the top of the condenser.

I The combination of features forming the invention may be utilized in a condenser as an integral part thereof, or may be incorporated in an adapter forming part of the condensing assembly and serving as a means for mounting the condenser in the kettle opening. In either case, the capacity of the distilling apparatus, with which condensing apparatus embodying the invention is used, may be greatly increased with complete safety.

For a better understanding of the invention, reference may be made to the accompanying drawing, in which:

FIG. 1 is a view, partly in elevation and partly in vertical section, of one form of reflux condenser embodying the invention;

FIG. 2 is a view in vertical section of a part of a modified form of the condenser of the invention; and

FIG. 3 is a view in vertical section showing the invention embodied in condensing apparatus including a condenser and an adapter.

The condenser shown in FIG. 1 is generally of conventional construction and it includes a hollow shell of glass having an open neck 11 at its upper end provided with an internal tapered seat, in which supplementary equipment may be mounted in the usual way, if de- 3,015,474 Patented Jan. 2, 1962 sired. At its lower end, the shell has a tubular extension 12 formed at its end with an external conical surface adapted to mate with an internal seat in the neck 13 of a kettle 14 to form a standard tapered joint. The shell encloses a coil 15 for the cooling medium and the ends 15a, 15b of the coil extend through the wall of the shell.

A vapor tube 16 lies within the lower end of the shell below the coil 15 and is attached to the wall of the shell around the opening leading to the extension 12, so that the tube is, in effect, an upward continuation of the extension. An opening 16a is formed through the wall of the tube 16 immediately adjacent to the junction of the tube 16 with the wall of the shell, and a condensate return tube 17 is attached to the tube 16 and the wall of the shell around the opening 16a. The return tube 17 leads from the opening through the extension 12 to terminate beyond the lower end of the extension.

In the use of the condenser shown in FIG. 1, the tubular extension 12 is inserted into the neck of the kettle 14 until the conical surface on the extension engages the internal seat in the neck and, when the condenser is thus supported, the lower end of the condensate return tube 17 extends into the kettle below the neck. The boiling of liquid within the kettle 14 causes the vapor to pass upward through the extension 12 and the vapor tube 16 into the body of the shell, where the vapor is condensed by contact with the cooling coil 15. The condensate travels downwardly through the shell to collect in the annular space 18 surrounding the tube 16 and the condensate escapes from the annular space through the return tube 17. As the return tube terminates within the kettle 14 at a point where the cross-section of the kettle is relatively large, the vapor velocity at this point is low and the condensate is free to fall into the vessel counter-current to the rising vapor. Any condensate, which enters the vapor tube 16, will flow down through the tube and the extension 12 and enter the kettle, if the vapor velocity of the vapor traveling upward through the extension and tube is relatively low. When the vapor velocity in tube 16 is high, that part of the condensate which enters the vapor tube 16, will be blown upward by the vapor and will, ultimately, land upon an inner Wall of the condenser shell, after which the condensate will flow downward along the shell and enter the annular space 18.

In the modified construction illustrated in FIG. 2, the shell 19 of the condenser is formed with a tubular extension 20, which has a conical section 29a at its lower end adapted to be received in a seat in the neck 21 of a kettle 22 to form a tapered joint. The conical section 29a has an opening 23 through its wall near its lower end and it is substantially longer than the neck 21 on the kettle, so that, when the section is in firm engagement with the seat irl the neck, the lower end of section 20a and the opening 23 lie within the kettle. At its lower end, the section Zita has an internal flange defining an opening and a vapor tube 24 is connected to the inner edge of the flange around the opening and extends upward through extension 26 and into the shell 19 of the condenser to terminate somewhat below the cooling coil 25.

The condenser illustrated in FIG. 2 functions in the same manner as that of FIG. 1, in that vapors enter the opening at the lower end of section 2011 of extension 2% and travel upwardly through tube 2- into the shell 19, where condensation occurs. The major portion of the condensate travels downwardly around the outer portion of the vapor tube 24 and enters the annular space 26 around the lower end of the tube, the condensate escaping from this space into the kettle through the opening 23. Any condensate, which enters the upper end of tube 24, may pass downward through the tube and enter the kettle when the vapor velocity in tube 24 is low, but, when the velocity of the vapor is high, the condensate is blown against the inner surface of the shell and flows down into the annular space 26. As in the condenser of FIG. 1, the condensate entering the kettle through opening 23 is out of contact with the vapors passing upward through the vapor tube 24.

The condensing apparatus shown in FIG. 3 includes a standard condenser having a shell 27 with an extension 23 at its lower end provided with a conical section 28a with an external seat. The condenser includes the usual cooling coil 29. The apparatus further includes an adapter, which is a hollow member 36 having a neck 31 at its upper end formed with an internal seat adapted to form a tapered joint with the external seat on the end section 28a of extension 23. The member 39 has a tubular extension 32 at its lower end and the extension is pr vided with a conical end section 32a having an external surface adapted to be received in the seat of the neck of a kettle to form a tapered joint. A vapor tube 33, which is similar to the tube 16 of the condenser of FIG. 1, leads upward from the opening at the bottom of the hollow member 30 and an opening 33a is formed in the wall of the tube adjacent its connection to the wall of themember. A condensate return tube 34 similar to tube 17 leads downward through extension 32 from the opening 324: and terminates beyond the lower end of the extension. The apparatus of FIG. 3 functions in the same manner as that shown in FIG. 1. The purpose of the adapter is to make it possible to attach a conventional condenser having wide enough passages to be immune to flooding at the expected distillation rates to a kettle with an opening narrow enough to cause flooding when connected directly to a conventional condenser .with a bottom tube of matching size.

To make clear the advantages of condensing apparatus embodying the invention, a series of tests were made, in which use was made of a conventional condenser and a second condenser of the same size as the first, but of the construction shown in FIG. 1. These condensers were joined to a kettle containing carbon tetrachloride and heated by resistance heaters and the power input to the heaters was controlled and the wattage noted. In such a case, it is well known that the wattage supplied to the heaters may be taken as a measure of the rate, referred to as the boilalp rate, at which vapor enters the condenser and the condensate leaves it.

In the tests, the wattage supplied to the heaters was increased until the conventional condenser flooded at 640 watts. The heating was then further increased, until it was found that the condenser of the FIG. 1 construction performed satisfactorily at 1860 watts, which was the wattage limit of the heaters used. 'Assuming no heat loss to the atmosphere, it is apparent that the new condenser may be operated without flooding at a boil-up rate,

which is greater than that of a standard condenser by at least the factor of FIG. 1 as compared with thecondenser of FIG. 2 results from the use in the FIG. 1 construction of a vapor tube 16, which is substantially greater in diameter than the COIIeSPOIIdiHg ube .24 of the FIG. 2 construction.

Iowever, the construction of the condenser of FIG. 2 is somewhat sturdier than that of the condenser of FIG. 1, so that, where the boil-up requirements are less severe, it is to be preferred.

The performance of condensing apparatusof the type shown in FIG. 3 is approximately the same as that of a condenser of the FIG. 1 construction and of the same size, since the vapor tube 33 and the condensate return tube 34 of the adapter are substantially the same as the corresponding parts 16 and 17 of the condenser of FIG. 1.

The condensers and the adapter illustrated have been shown with parts, by which they may be connected to kettles with standard tapered joints, but it is to be understood that any of the other standard joints, such as ball joints and flange joints, or those made by stoppers may be used, if preferred. Also, while the combination of the vapor and condensate return tubes has been described in its use in condensing apparatus, the combination may be employed advantageously in other apparatus, such as gas scrubbers. Moreover, although coil condensers have been used in the examples, the arrangement for avoiding flooding at the joint between the condenser to the kettle may advantageously be attached to any condenser possessing adequate condensing area and adequate passages within the hollow shell portion.

I claim:

1. A refluxing apparatus which comprises a vessel for containing a'liquid, the vessel having a single opening for escape of vapor and for introduction ofliquid, a liquidcollecting cooling and condensing member having an opening for escape of liquid. and for introduction of vapor, a connection between the respective vessel and member openings, the connection including inner and outer substantially concentric tubes, the outer tube extending from the vessel opening through the member opening toterminate in the interior of the condensing member above the member opening, said outer tube having an opening through its wall close to and above the member opening, the upper end of said inner tube communicating with the upper tube wall opening, and the lower end of said tube projecting beyond the lower end of said outer tube to terminate in the vapor space within the'vessel below the vessel opening.

2. Apparatus according to claim 1 in which said outer tube conducts vapor from the vessel into the interior of said condensing member and said inner tube conducts liquid from said condensing member into said vessel.

3. A reflux apparatus for connection to a vessel containing a boiling liquid, said vessel having a common opening for the egress of vapor produced by boiling said liquid and for the introduction of liquid condensate into said vessel,'said reflux apparatus comprising a cooling means for condensing vapor to liquid, means for interconnecting said cooling means and said vessel opening, said interconnection having concentric inner and outer passages, the portion of said cooling means adjacent said interconnecting means having concentric inner and outer passages, the inner passage of said interconnecting means communicating with the outer passage of said cooling means to provide liquid transfer from said cooling means to said vessel, the outer passage of said interconnecting means communicating with the inner passage of said cooling means to provide vapor transfer from said vessel to said cooling means, the inner passage of said interconnecting means being formed by a tube whose lower end terminates in the vapor space of said vessel below the vessel opening.

4. A reflux apparatus for connection to a vessel containing a boiling liquid, said vessel having a common opening for the egress of vapor produced by boiling said liquid and for the introduction of liquid condensate into said vessel, said reflux apparatus comprising a cooling means for condensing vapor to liquid, means for interconnecting said cooling means and said vessel opening, said interconnection having a first upper pair of inner and outer concentric tubes and a second lower pair of inner and outer concentric tubes, the lower inner tube communicating with the upper cuter tube to provide liquid condensate transfer from said cooling means to said vessel, and the lower outer tube communicating with the upper inner tube to provide vapor transfer from said vessel to said cooling means, the lower end of said lower inner tube terminating in the vapor space within the vessel below the vessel opening.

5. In a refluxing system having a liquid collecting cooling and condensing member, and a vessel for containing a boiling liquid, said vessel having a common opening for the egress of vapor produced by boiling said liquid and for the introduction of liquid condensate into said vessel, the improvement comprising an interconnection between said condensing member and the vessel opening, said interconnection having a first upper pair of inner and outer concentric tubes and a second lower pair of inner and outer concentric tubes, the lower inner tube communicating with the upper outer tube to provide liquid condensate transfer from said cooling means to said vessel, and the lower outer tube communicating with the upper inner tube to provide vapor transfer from said vessel to said cooling means, the lower end of said lower inner tube terminating in the vapor space within the vessel below the vessel opening.

6. A reflux apparatus for connection to a vessel containing a boiling liquid, said vessel having a common opening for the egress of vapor produced by boiling said liquid and for the introduction of liquid condensate into said vessel, said reflux apparatus comprising a cooling means for condensing vapor to liquid, means for interconnecting said cooling means and said vessel opening, said interconnection having a first upper pair of inner and outer concentric tubes and a second lower pair of inner and outer concentric tubes, the lower inner tube communicating with the upper outer tube to form a liquid passage from said cooling means to said vessel, and the lower outer tube communicating with the upper inner tube to form a vapor passage from said vessel to said cooling means, said liquid passage being isolated from said vapor passage, the lower end of said lower inner tube terminating in the vapor space within the vessel below the vessel opening.

References Cited in the file of this patent UNITED STATES PATENTS 1,082,304 Cary-Curr Dec. 23, 1913 1,317,262 Bajda Sept. 30, 1919 1,663,047 Gray Mar. 20, 1928 1,668,769 Hering May 8, 1928 2,425,669 Brock Aug. 12, 1947 2,537,942 Martin Ian. 9, 1951 2,683,333 Canicoba July 13, 1954 2,701,789 White Feb. 8, 1955 2,804,292 Schilling Aug. 27, 1957 FOREIGN FATEiJTS Germany Oct. 8, 1921 

